I have the same car... came with Hankook Optima 418's .... nice tire in the dry. We had our first snow yesterday. Seem ok in light snow but I would think anything more than a few inches would they would be junk. I would recommend a set of Goodyear Eagle Ultra Grip Ice. The single best tire I have ever owned.
They will be going on as soon as I get some steel rims for winter.